Companies like Infosys, TCS, Wipro, Satyam, HCL, EDS, Accenture, Sun Microsystems and HP are based in the city’s software and biotech parks. Software exports of Rs.1,442,140 million during 2006–07, earned name for Chennai as a second-largest exporter of software in the country, behind Bangalore.

The Industrial hub of South India, Chennai, has about 45% of India's auto components and 27% of the vehicle industry. Chennai houses various manufacturing units of various automobile giants across the globe like Mitsubishi, Ford, Hyundai, Ashok Leyland, Royal Enfield, TAFE, MRF, Dunlop as well as TI Cycles to name a few. The Integral Coach Factory manufactures railway coaches and other rolling stock for Indian Railways. Chennai has acquired the name as being the "Detroit of Southern Asia". This was possible because of such an industrial expanse.

India's leather exports constitute a share of more than 50% that comes from Chennai. An SEZ (Special Economy Zone) has been set up which manufactures apparels and footwear. The said SEZ is located in the southern suburbs of the city. Chennai has an electronics manufacturing hub. This is a place where many MNC’s have set up electronics and hardware manufacturing plants. Nokia, Motorola, Samsung, Dell, Flextronics and Foxconn are major examples in that case. Research and Development facilities have also been set up in Chennai. Various chemicals giant Dow Chemicals, pharmaceuticals giant like Pfizer alongwith the telecom giants like Ericsson and Alcatel-Lucent would be to name a few.

Chennai is seat of prominent financial institutions, including the World Bank, HSBC, Citi Bank. Chennai holds three large national level commercial banks and many state level co-operative banks, finance and insurance companies.

Apollo Hospitals, the largest private healthcare provider in Asia, is based in Chennai. Also some of India's well-known healthcare institutions such as 'Sankara Nethralaya' and 'Sri Ramachandra Medical Centre' are based in the city. With the presence of these & many more renowned institutions offering world class care and cure within everybody's reach makes Chennai the most preferred place for medical tourism across the globe.

Number of SSI’s (Small Scale Industries) has been established in Chennai availing the good facilities provided by the city. Moreover, industrial units also have been set up in Chennai due to its very liberal policy. Expectedly, by 2025, Chennai's economy would increase to about $150 billion from the current $45 billion.